Combine development in recent years have put greater demands on the straw choppers and chaff spreaders. The main reasons are that larger combines and wider cutting widths are creating higher flows of straw and chaff; wider cutting widths create more demanding spreading widths; reduced tilling practices have put more demand on even spreading of both straw and chaff and that plant breeding has resulted in tougher straw, higher yields and more residue.
Farmers are demanding straw and chaff spreading systems that will allow them to adjust or operate the combine to select one of the following options, depending upon the requirements at that time:
Spread the straw and chaff evenly over the entire cutting widths of the combine which are now up to 42 feet;
Windrow the straw and chaff together to be bailed at a later date;
Windrow only the straw and spread the chaff; or
Spread the straw and collect the chaff to be used at a later date
Current methods to spread chaff are costly and require additional horsepower and components, that is chaff spinners or fans to boost chaff into chopper.
Some current combines spread chaff through the straw chopper when straw is spread, however when straw is windrowed over the chopper's tailboard the fins are lowered and a wide spread of the chaff is not possible due to the orientation of the fins directing the chaff into the ground
Rekord in a publication now WO Patent Application Publication No. 03/071857 describing their Combi system provides an arrangement in which the chaff spinner can be directed to either spread laterally so as to separate from the straw or it can be set to boost the chaff into the straw chopper or the windrowed straw.
Rekord in a publication describing their Rekord Plus system provides an arrangement in which the chaff spinners are mounted under the straw chopper and the output of the spinners utilize the chopper's tailboard for disbursement of the chaff
New Holland in a publication describing their CX Combine provides an arrangement in which the chaff is blown into the straw chopper when the straw is windrowed over the tailboard.
U.S. Pat. No. 4,218,022 (VOEHM) issued Aug. 19, 1980 to Gebr. Eicher GmbH discloses a straw chopper and spreader of the type having a rotating rotor with flail blades rotating about a horizontal axis over a floor of the chopper where fins are attached to the floor of the chopper housing at a position adjacent discharge opening. These fins are used in replaced for fins on a tailboard which are now more commonly used.
U.S. Pat. No. 6,331,142 (Bischoff) issued Dec. 18, 2001 to Deer and Company discloses a chopper of the same general type which has a floor panel at the discharge opening which can be adjusted in angle around a pivot axis parallel to the rotor axis and lying in the curvature of the floor so the discharge opening can be moved upwardly and downwardly. This panel is linked by a coupling to a tailboard carrying spreading fins so that an adjustment of one effects adjustment of the other.
US Application 2002/0086722 published Jul. 4, 2002 by Claas discloses an arrangement in which there is provided a straw and chaff chopper and distributor formed by a rotor rotating about a horizontal axis where the chopper includes as part of the structure a tailboard attached thereto. The tailboard can be tilted downwardly and guides inside the harvester activated so that straw is feed over the top of the tailboard for swathing. At the same time the pivotal movement of the tailboard is combined with a pivotal movement of the chopper housing so that the chopper discharges at the required angle to the tail board since the housing is pivoted with the tailboard.
U.S. Pat. No. 6,656,038 (PERSSON) issued Dec. 2, 2003 to Rekordverken discloses a chaff spinner formed by a pair of rotors behind the sieve which can be rotated to position where the chaff is blown into a chopper behind the chaff spinner to be spread with the straw.